Shower sump pump (rule 800) stopped pumping. When pump disconnected it works fine. When connected it runs but doesn't pump.Water even shoots out of the pump head. It runs 6 ft to a vented loop and then to discharge. Worked fine for years. Because all hoses and fittings are very hard to access I'd like to get suggestions as to where to start and what the problem could be. Thanks in advance.

When you say the pump runs fine when disconnected, do you mean that you can put the pump in water and the pump will pump the water up and out a hose or you can just hear the motor run and seen the rotor turn? If you can actually pump water with the pump when disconnected but connect it and water sprays out at the pump but doesn't go out the discharge hose I would suspect the discharge hose is blocked.

Disconnect the discharge hose and blow through it to see if it's free. If you can't reach the end of the hose rig a short piece of hose temporarily to the discharge hose maybe with a piece of tape for the test.

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The water is always bluer on the other side of the ocean.

Pump does discharge water when hooked up to a temporary hose. The consensus with both your answers then is a clogged discharge hose as opposed to a problem with vented loop. Boat was just hauled so hopefully not be a problem with thru hull outlet.

The vented loop keeps water from siphoning back into your boat after the pump shuts off. if vent was clogged it will have no effect on the pump pumping out water. If the pump pumps water through a different hose then you definitely have an obstruction somewhere. Again most likely at the through hull.

If there isn't a blockage, the pump impeller may be slipping on the shaft. The pump would move water with little or no head but not be able to push water high enough to get over the loop. If that is the case, replace the pump.Non-Automatic Submersible Pump 800 GPH 12 Volt

If there isn't a blockage, the pump impeller may be slipping on the shaft. The pump would move water with little or no head but not be able to push water high enough to get over the loop. If that is the case, replace the pump.Non-Automatic Submersible Pump 800 GPH 12 Volt

That was my second thought as well.

By the way, enjoyed the chat when I came by your store a couple weeks back. Catch you again the next time I'm in Miami.

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The water is always bluer on the other side of the ocean.

On the pump outlet that takes the tube you will see a small 1/32 hole at the top. This is for self priming. This little hole gets blocked buy soap scum and makes it difficult to prime. Or the hose is pushed to far on and covers the hole. What i did was drill it out to 1/8 and have had no problems since.

Blue Moon—a 2013 Oceanis 48—has a shower sump in the master cabin which is equipped with both a float switch and a manual button. As in the aft head/shower (which has no float switch) the manual button runs the sump for 15 seconds each time you push it.

The first time the master shower sump quit working, it was repaired under warranty. We do not know what was actually done. Now, six months later, it has failed again. Our attempts to tease out the origin of the problem reveal that it has failed in a rather odd way.

If you shut down power to that shower sump circuit by popping the breaker, as soon as power is reapplied, the sump runs for 13-15 seconds—then quits. The only way to get it to run again is to interrupt and reapply power to that circuit. We also did this by interrupting the entire 12V Domestic power circuit and then reestablishing it. Same result.

These tests were all done with water in the shower pan so the presumption is that it was the float switch that was making the pump run. The manual button was never pushed as a part of the testing other than after the pump stopped at which time it had no effect. Interestingly, the pump timing relay is programmed to apply power for 15 seconds in response to a button push. The float switch (when working correctly) will allow the pump to run continuously as long as water is present.

The tank? On this boat, there is a ˝" hose that leads from a depression (where the float switch is) in the shower floor up behind the master cabin sink to the pump. I cannot say that I have inspected every inch of that line nut most of it is visible. I don't think there is a tank in that loop.

When mine plugs up, I disconnect the discharge house and use my dinghy air pump to blow out the line. High volume of air and not to much pressure. If that doesn't work, I have a piece of rigging wire I use as a snake. I have a check valve in line, and that sometimes gets munged up.